// (c) Copyright Ascensio System SIA 2010-2022
//
// This program is a free software product.
// You can redistribute it and/or modify it under the terms
// of the GNU Affero General Public License (AGPL) version 3 as published by the Free Software
// Foundation. In accordance with Section 7(a) of the GNU AGPL its Section 15 shall be amended
// to the effect that Ascensio System SIA expressly excludes the warranty of non-infringement of
// any third-party rights.
//
// This program is distributed WITHOUT ANY WARRANTY, without even the implied warranty
// of MERCHANTABILITY or FITNESS FOR A PARTICULAR  PURPOSE. For details, see
// the GNU AGPL at: http://www.gnu.org/licenses/agpl-3.0.html
//
// You can contact Ascensio System SIA at Lubanas st. 125a-25, Riga, Latvia, EU, LV-1021.
//
// The  interactive user interfaces in modified source and object code versions of the Program must
// display Appropriate Legal Notices, as required under Section 5 of the GNU AGPL version 3.
//
// Pursuant to Section 7(b) of the License you must retain the original Product logo when
// distributing the program. Pursuant to Section 7(e) we decline to grant you any rights under
// trademark law for use of our trademarks.
//
// All the Product's GUI elements, including illustrations and icon sets, as well as technical writing
// content are licensed under the terms of the Creative Commons Attribution-ShareAlike 4.0
// International. See the License terms at http://creativecommons.org/licenses/by-sa/4.0/legalcode

namespace ASC.Web.Core.Mobile;

[Scope]
public class MobileDetector
{
    private readonly Regex _uaMobileRegex;
    private readonly ICache _cache;
    private readonly IHttpContextAccessor _httpContextAccessor;

    public bool IsMobile()
    {
        return IsRequestMatchesMobile();
    }


    public MobileDetector(IHttpContextAccessor httpContextAccessor, IConfiguration configuration, ICache cache)
    {
        this._cache = cache;
        if (!string.IsNullOrEmpty(configuration["mobile:regex"]))
        {
            _uaMobileRegex = new Regex(configuration["mobile:regex"], RegexOptions.IgnoreCase | RegexOptions.Singleline | RegexOptions.Compiled);
        }

        _httpContextAccessor = httpContextAccessor;
    }


    public bool IsRequestMatchesMobile()
    {
        bool? result = false;
        var ua = _httpContextAccessor.HttpContext.Request.Headers["User-Agent"].ToString();
        var regex = _uaMobileRegex;
        if (!string.IsNullOrEmpty(ua) && regex != null)
        {
            var key = "mobileDetector/" + ua.GetHashCode();


            if (bool.TryParse(_cache.Get<string>(key), out var fromCache))
            {
                result = fromCache;
            }
            else
            {
                result = regex.IsMatch(ua);
                _cache.Insert(key, result.ToString(), TimeSpan.FromMinutes(10));
            }
        }
        return result.GetValueOrDefault();
    }
}
